“It’s one of the coolest places on earth,” he said. “People tend to forget there is this big productive research facility that chugs away all night long up there.”

The former public affairs director for Palomar — he left last year to take the same post with the International Dark Sky Association in Tucson — will share his passion for the observatory during a lecture, “Palomar Observatory: Past, Present and Future,” 7:30 p.m. Friday in the Borrego Springs Performing Arts Center to kick off the third annual Borrego Energy Day 2012. The full-day Saturday event includes workshops, demonstrations and films focused on energy conservation and alternatives.

The event is sponsored by the Anza-Borrego Desert Natural History Association.

“Borrego Springs is a forward-looking community, so looking ahead to how we will be dealing with energy in the future is a fascinating thing,” said Betsy Knaak, the association’s executive director. “It is very hot here six months out of the year, so energy and how to use the benefits of that sun are important issues to us.”

In addition to sunny days, Borrego Springs is known for its starry nights. During the latter part of Kardel’s eight years at Palomar, he helped write the town’s successful application to be named the second International Dark Sky Community in the U.S., recognizing Borrego’s efforts to maintain natural light. In addition to his Friday night talk, Kardel on Saturday will introduce the first U.S. screening of a subtitled Korean documentary, “For Those Denied the Sky,” that was filmed in Borrego Springs to explain the significance of vanishing dark skies.

Kardel, who has a master’s degree in astronomy, will touch on the dark sky phenomenon during his Friday lecture, too, but the focus of that presentation will be on what he calls the “epic project” that ensued to create the 200-inch Hale Telescope at Palomar during the Great Depression era. It was completed in 1948.

“This is very much a human story,” Kardel said. “It shows off the faces of the people who made it happen when you look at them and see the conditions they were working under. They routinely placed themselves in peril.”

The Hale Telescope was the largest telescope in the world for decades. Although it has now been surpassed, researchers continue a 24/7 slate of projects from the observatory.

“Probably the most wide-open field right now is the hunt for planets around other stars,” Kardel said. “The big telescope at Palomar is being used to hunt for them. Eventually it will tell us if there are other worlds like Earth.”

Kardel said his Friday presentation will include seldom-seen photos of the observatory construction and other artifacts, but he was careful to point out that the lecture won’t be technical.

“There won’t be any graphs; no math,” he said. “It will be a fun look at how this place came together and the cool stuff they’ve been doing there since.”

The lecture is free to Anza-Borrego Desert Natural History Association members and $5 for nonmembers. Limited seating is first-come.

Saturday’s Borrego Energy Day events will be at the Borrego Desert Nature Center and include: